1. Field of the Invention
The present invention relates to an air conditioner, and particularly, to a service valve assembly and an air conditioner having the same capable of decreasing a flow passage resistance of a refrigerant and simplifying the construction of the air conditioner by coupling an outer filter drier to the air conditioner at the time of installation thereof or after-sales service therefor, filtering foreign materials such as moisture, welding oxide, or the like in a refrigerant pipe, and separating the filter drier from the air conditioner after completing the operation.
2. Background of the Related Art
In general, an air conditioner is used to maintain temperature, humidity, cleanliness, or the like to be appropriate for the use of areas, and to eliminate dust or harmful gas. For using it as a cooling apparatus, the air conditioner forms a cycle of absorbing indoor heat to maintain the inside at a low temperature, and then discharging the absorbed heat to the exterior.
As an example of the air conditioner, a multi-air conditioner, as shown in FIG. 1, comprises an outdoor unit 10 including a compressor 12 and an outdoor heat exchanger 14, an indoor unit 30 including an indoor heat exchanger 31 disposed at each indoor space, and a distributing unit 20 including distribution valves 21 and 22 for connecting or blocking a passage between each indoor heat exchanger 31 and the outdoor unit 10.
An operational principle of the multi-air conditioner will now be explained hereafter. In case of a complete cooling operation for operating every indoor unit in a cooling mode, the indoor heat exchanger 31 functions as an evaporator, and the outdoor heat exchanger 14 functions as a condenser. A refrigerant sequentially passes through the compressor 12, a four-way valve 13 and the outdoor heat exchanger 14 of the outdoor unit 10. The refrigerant then passes through an expansion valve 32 and the indoor heat exchanger 31 in each indoor unit 30 along a liquid line. Thereafter, the refrigerant is retrieved into an accumulator 11 along a low pressure vapor line 25. The refrigerant is then divided into vapor and liquid to be delivered to the compressor 12.
In case of a complete heating operation for operating every indoor unit in a heating mode, on the other hand, the indoor heat exchanger 31 functions as the condenser, and the outdoor heat exchanger 14 functions as the evaporator. The refrigerant passes through the compressor 12 along a high pressure vapor line 24 and is heat-exchanged in the indoor heat exchanger 14. The refrigerant then passes through an expansion valve 15, the indoor heat exchanger 14 and the four-way valve 13 along the liquid line 23 to be retrieved into the accumulator 11. The refrigerant is then delivered to the compressor 12 again.
In the multi-air conditioner having such construction and principle, after the installation or repair service thereof, upon operating the multi-air conditioner, the refrigerant starts to circulate. Here, foreign materials such as moisture, welding oxide or the like within each connected refrigerant pipe circulate within the multi-air conditioner together with the refrigerant, and thereby are accumulated in the compressor 12 or the expansion valves 15 and 32. In order to prevent the accumulation of the foreign materials, a filter (strainer) 18 is disposed at an upstream side of the compressor 12, based upon the flow of the refrigerant, and a similar apparatus (not shown) thereto is disposed at an upstream side of the expansion valves 15 and 32.
While driving the multi-air conditioner having such construction, the filter 18 is continuously mounted at a circulating system of the refrigerant. Accordingly, foreign materials accumulated in the filter 18 increase a flow passage resistance due to the refrigerant being circulated, which causes a freezing of the refrigerant, thereby decreasing the performance of the multi-air conditioner.
In order to reduce a mechanical friction of the compressor 12 and prevent the generation of heat, on the other hand, lubricating oil is mixed with the refrigerant for use. While performing a vacuum operation, if moisture contained in the refrigerant is not completely removed, the moisture is absorbed by the refrigerant and the lubricating oil to thereafter be an icy grain, which then causes various mechanical problems. Accordingly, a drier 17 is mounted in parallel in the liquid line 23 in order to completely remove the moisture contained in the refrigerant and the lubricating oil being circulated.
The drier 17 does not have to be continuously disposed in the multi-air conditioner as the apparatus for removing the moisture after installing the multi-air conditioner or after-sales services. For being continuously mounted, deterioration of the drier 17 may cause a decrease in performance of the multi-air conditioner and the construction of the multi-air conditioner system may be complicated.